Catering trucks require hot water for two purposes. One is to heat the food in the steam table and the other is for washing dishes and general cleaning purposes. Heretofore, catering trucks employed separate burners to provide the hot water required. One burner was in a hot water heater and was used to supply hot water for the sink. This hot water heater was generally mounted outside the truck. The other burner was mounted inside the truck and was used to heat the water in the steam table for heating the food. The burner in the hot water heater mounted outside the truck was exposed to dirt kicked up from the road, rain, and corrosion, which caused the burner to become unreliable. When the hot water heater failed, the source of hot water for cleaning purposes stopped. Since laws regulating the operation of catering trucks require a constant source of hot water as a condition for doing business, a failure in the hot water heater stopped business until the hot water heater could be fixed. In addition, the hot water heater heretofore required a battery operated electric pump to move the water to the steam table from the hot water tank. This also created problems because, if the pump was operating while the motor was off, the battery would run down, causing the pump to stop and under some circumstances prevent the truck from starting. In either case, business had to stop until hot water could again be supplied to the sink. Of course, the motor in the truck could be left operating to keep the battery charged while the truck was doing business, but this is prohibitively expensive, particularly since the cost of fuel has risen so high.
The hot water from the water heater, which is connected to the sink, must be supplied with sufficient pressure. This made attempts to put a water tank in the form of coiled tubing connected to the hot water heater, in, under, or along side the steam table so that the heated water in the coiled tubing could heat the water in the steam table and supply heated water to the sink, impractical. This is because the turns of the coiled tubing increased water friction to such an extent that it required a large, expensive pump to force the water through the tube into the sink at a useful water pressure. This arrangement also eliminated the practical possibility of using gravity to force water through the coiled tubing to the sink in order to eliminate the expense and reliability problems inherent in a water pump.
What is needed, therefore, and comprises an important object of this invention, is to provide a catering truck with a steam table which has a reliable source of hot water and which is not affected by road or atmospheric conditions.
Another object of this invention is to provide a hot water supply for heating food in a catering truck and for providing a source of hot water for a sink which is economical to manufacture, reliable, and which does not require any moving parts and which saves gas.
Yet another object of this invention is to provide a steam table for a catering truck which utilizes a gravity feed in combination with a single source of heat for providing hot water for the sink at a useful pressure and which provides the heat for the water inside the steam table.
This is now accomplished in the steam table described herein, wherein the steam table is an open top tank adapted to be filled with water. The tank is designed to hold containers of food which are heated by the water in the tank. The tank has a double bottom which contains water separate from the water in the steam table. Heat is supplied to the water in the double bottom which heats the water contained in the open top tank. The heated water in the double bottom is also connected to a sink and provides a source of hot water for cleaning. The number of obstructions inside the double bottom tank is minimal so that gravity is practical for forcing water through the double bottom tank to the sink at a useful pressure. In this way, a single burner protectively mounted inside the truck is used to heat the steam table and supply hot water at a useful pressure to the sink .